1. Field of the Invention
The present invention relates to a system for making discriminations between cartridges for housing toners to be equipped on image forming apparatus such as electrostatic copiers, laser beam printers, facsimiles, etc.
2. Description of the Prior Art
Supplementing toner into an image forming apparatus such as aforementioned is done in many cases with a cartridge housing toners therein (hereinafter merely referred to as cartridge) loaded in a cartridge inserting part of the image forming apparatus.
Such a cartridge is sealed on its toner supplementing port with a flexible sheet folded in two plies. Accordingly, when supplementing the toner, this cartridge is loaded in the cartridge inserting part such as a toner hopper, etc., on the developing device side. Thereafter, the toner supplementing port is unsealed by stripping off the aforementioned flexible sheet by pulling its turned-up portion, thereby charging the toner into the toner hopper.
Such a conventional toner supplementing device involved following problems:
Conventional toner supplementing devices are of a structure such that even if the loading of a cartridge in a toner hopper is somewhat imperfect, the flexible sheet is strippable. For this reason, the toner supplementing port will be sometimes inadvertently unsealed, not withstanding the cartridge has not been properly loaded. As the consequence, the toner sometimes scatters through clearances. Particularly, during the image treating operation, the toner has sometimes been blown and leaked out due to the cooling air inside the image forming apparatus or the revolution of toner supplementing rollers, etc.
Cartridges are often so composed as to have a common size, so that their components may be put to common use with different types of image forming apparatuses. Accordingly, when various types of image forming apparatuses are available, there has been a possibility of supplementing toners which are different in properties and color, etc.